Tenter frame sequential biaxial orientation process is one of the common fabrication processes in the polymer film industry. In this process, polymers are oriented in the semi-solid state, which is significantly different from the orientation in the molten state, as occurs in traditional blown film or cast film processes. Most physical properties, including clarity, stiffness and toughness, are dramatically improved upon the semi-solid state orientation. Polymers that can be processed by the tenter frame include polypropylene (PP), polyethylene terephthalate (PET), and polyamide (PA). However, currently available polyethylenes cannot be oriented by the tenter frame process, due to their poor stretchability.